Step 6: Melting wax out of ceramic shell mold
and then pouring hot bronze into the empty mold

(Please scroll down until you
come to "Next Step")

Before melting the wax out of the ceramic shell
mold, the bottom of the sprue cup is removed with a grinder.

The owl is then put into an oven.
In this oven the wax will melt and the ceramic shell will harden so that it is very
similar to porcelain. The owl is positioned with the sprue cup facing down, so
that when the oven is heated, the melted wax will drain out. Wax that doesn't
drain will burn.

These hot molds are placed in a sand pit with
the sprue cup facing up. Now, empty, the cup becomes a funnel. What were wax
sprues, attaching the cup to the owl, are now empty channels for the melted bronze to flow
down into the owl form.

In a nearby furnace, the bronze has already
been melted. It is in a heat resistant container called a crucible.
It takes two strong and coordinated people to lift the full crucible up with a special
four handled clamp. Careful attention is given to the temperature of the
molten bronze before the pouring captain gives orders to pour the glowing liquid metal
into the still hot ceramic mold.

Depending on the thickness of what the wax was,
the molten bronze is heated to between 1,800 and 2,150 degrees Fahrenheit before being
poured. Thinner forms are poured at hotter temperatures.

The bronze is now cooling in these filled
molds. Everything that was wax, is now bronze!